الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
In the high-voltage direct current (HVDC) transmission system, Converters are considered to be the main sources of harmonics due to the commutating process. Passive and active filtering approaches are considered to be proper harmonic mitigation techniques which are applied in various power systems. Filters are placed in the converter transformer primary side in the traditional high-voltage direct current (HVDC) transmission system to decrease the negative effect of converter harmonics on the AC system. This thesis focuses on the effect of an inductive filtering method on reducing harmonics for HVDC system. A double-tuned filter is installed at the linking point between the prolonged winding and the common winding of the converter transformer secondary side. To reduce the inductive harmonic current in the primary winding, a proper design of the double-tuned filter is presented. At the moment the harmonic current passes through the prolonged winding, the common winding will induct harmonic current in the opposite direction to balance it. The 5th, 7th, 11th and 13th harmonic components of current wave are suppressed in the converter transformer secondary side. Two models are constructed in Matlab/Simulink software package and simulated under different case studies. Also, the effect of changing converter transformer connection when using different inductive filtering technique combinations is illustrated. The study of the effect of using double tuned filter inside transformer secondary prolonged windings which is introduced in this thesis shows that harmonic currents are suppressed in the primary windings and the negative effect of harmonic currents on the converter transformer is decreased which cannot be achieved by the traditional converter transformer and installed ac passive filters in primary side.